science grade 07 unit 12 exemplar lesson 02: changes in ...staar note: student expectation 7.11c is...

Grade 7

Science

Unit: 12

Lesson: 02

Suggested Duration: 7 days

Science Grade 07 Unit 12 Exemplar Lesson 02: Changes in Genetic TraitsScience Grade 07 Unit 12 Exemplar Lesson 02: Changes in Genetic Traits

This lesson is one approach to teaching the State Standards associated with this unit. Districts are encouraged to customize this lesson by

supplementing with district-approved resources, materials, and activities to best meet the needs of learners. The duration for this lesson is only a

recommendation, and districts may modify the time frame to meet students’ needs. To better understand how your district may be implementingCSCOPE lessons, please contact your child’s teacher. (For your convenience, please find linked the TEA Commissioner’s List of State Board of

Education Approved Instructional Resources and Midcycle State Adopted Instructional Materials.)

Lesson Synopsis

Students will identify and explain variation within a population or species, as well as identifying some changes in genetic traits that have occurred over

several generations through natural selection and selective breeding.

TEKS

The Texas Essential Knowledge and Skills (TEKS) listed below are the standards adopted by the State Board of Education, which are required by

Texas law. Any standard that has a strike-through (e.g. sample phrase) indicates that portion of the standard is taught in a previous or subsequent unit.

The TEKS are available on the Texas Education Agency website at http://www.tea.state.tx.us/index2.aspx?id=6148.

7.11 Organisms and environments. The student knows that populations and species demonstrate variation and inherit many

of their unique traits through gradual processes over many generations. The student is expected to:

7.11B Explain variation within a population or species by comparing external features, behaviors, or physiology of

organisms that enhance their survival such as migration, hibernation, or storage of food in a bulb.

7.11C Identify some changes in genetic traits that have occurred over several generations through natural selection

and selective breeding such as the Galapagos Medium Ground Finch (Geospiza fortis) or domestic animals.

Supporting Standard

Scientific Process TEKS

7.1 Scientific investigation and reasoning. The student, for at least 40% of the instructional time, conducts laboratory and

field investigations following safety procedures and environmentally appropriate and ethical practices. The student is

expected to:

7.1A Demonstrate safe practices during laboratory and field investigations as outlined in the Texas Safety Standards.

7.2 Scientific investigation and reasoning. The student uses scientific inquiry methods during laboratory and field

investigations. The student is expected to:

7.2E Analyze data to formulate reasonable explanations, communicate valid conclusions supported by the data, and

predict trends.

7.3 Scientific investigation and reasoning. The student uses critical thinking, scientific reasoning, and problem solving to

make informed decisions and knows the contributions of relevant scientists. The student is expected to:

7.3A In all fields of science, analyze, evaluate, and critique scientific explanations by using empirical evidence, logical

reasoning, and experimental and observational testing, including examining all sides of scientific evidence of

those scientific explanations, so as to encourage critical thinking by the student.

7.3D Relate the impact of research on scientific thought and society, including the history of science and contributions

of scientists as related to the content.

7.4 Scientific investigation and reasoning. The student knows how to use a variety of tools and safety equipment to conduct

science inquiry. The student is expected to:

7.4A Use appropriate tools to collect, record, and analyze information, including life science models, hand lens, stereoscopes, microscopes,

beakers, Petri dishes, microscope slides, graduated cylinders, test tubes, meter sticks, metric rulers, metric tape measures, timing devices,

hot plates, balances, thermometers, calculators, water test kits, computers, temperature and pH probes, collecting nets, insect traps, globes,

digital cameras, journals/notebooks, and other equipment as needed to teach the curriculum.

GETTING READY FOR INSTRUCTION

Performance Indicators

Grade 07 Science Unit 12 PI 02

Create an advertisement for a genetic engineering firm. In the advertisement, compare natural selection to selective breeding, and explain how variation in the species

enhances its survival.

Standard(s): 7.2E , 7.11B , 7.11C

ELPS ELPS.c.5F , ELPS.c.5G

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http://www.tea.state.tx.us/index2.aspx?id=6148

about:/module/standards/Tools/Browse?StandardId=108977












about:/module/standards/0/108893/standard.ashx





Key Understandings

Traits enhance an organism’s survival.— How do external features (structure/function), adaptations, and behaviors of organisms enhance their survival?— How do genetic traits change over several generations?— How does variation within a population or species enhance their survival?— What evidence do we have that traits of organisms have changed over time?— What role do traits play in natural selection?— What role do traits play in selective breeding?— How are natural selection and selective breeding similar and different?

Vocabulary of Instruction

structure

function

variation

adaptations

camouflage

migration

hibernation

phototropism

geotropism

appendages

natural selection

selective breeding

Materials

4 Corners posters from Engage activity

alligator clips (hardware-type, 1 per group)

beans (dried, 5 different types, 5 cups total, 5 of each type per group minimum)

binder clips (1 per group)

cardstock (1 half sheet per student)

chart paper (1 per class)

chopsticks (with pointed ends, 1 per group)

clothespins (spring-type, 1 per group)

colored pencils (1 package per group)

cups (paper, small, 1 per group)

dried lima beans (1 bag per class)

finch or small bird seed (1 box per class)

foam bowl (large,1 per group)

jelly beans or gum drops (1 bag per class)

marker (1 per teacher)

mini-marshmallows (1 bag per class)

newspaper (1 sheet per group)

paper (chart, 4 sheets per teacher)

paper (graph, 1 per student)

paper (plain, 4 sheets per group)

pencil (sharpened, 1 per group)

penny (1 per group)

pliers (1 per group)

pointed objects (4 different diameters, per group)

raisins (1 box per class)

resealable plastic bag (snack-size, 1 per group)

ruler (1 per group)

safety goggles (1 pair per student)

scissors ( 2 pairs per group)

six-sided number cube (1 per group)

sticky notes (3”x3”, 2 per group)straws (not flexible, 4 per group minimum)

tape (clear, 1 roll per group)

tape or glue (per class)

timing device (1 per group)

timing device (1 per teacher)

toothpicks(round, 6 per class)

tweezers or forceps (1 per group)

yarn (cut into 4 cm pieces, several per class)

Attachments

All attachments associated with this lesson are referenced in the body of the lesson. Due to considerations for grading or student assessment,

attachments that are connected with Performance Indicators or serve as answer keys are available in the district site and are not accessible on the

public website.

Handout: Plant Advanced Organizer (1 per student and 1 for projection)

Grade 7

Science

Unit: 12

Lesson: 02



http://files5.mycscope.us/072162233242019232010253175132019171105184045129/Download.ashx?hash=2.2

Teacher Resource: PowerPoint: Plants and Their Adaptations

Handout: Verbal Visual Vocabulary Cards (1 per student)

Handout: Animal Advanced Organizer (1 per student and 1 for projection)

Teacher Resource: PowerPoint: Animal Variations and Behaviors

Optional Teacher Resource: Migration and Hibernation SAMPLE

Teacher Resource: Migration, Hibernation, Dormancy, Phototropism, and Geotropism (see Advance Prepar

Handout: Variation Lab (1 per student and 1 for projection)

Teacher Resource: Natural Selection Lab KEY

Teacher Resource: Natural Selection Process (1 for projection)

Handout: Finicky Finches Lab (1 per student and 1 for projection)

Teacher Resource: Finicky Finches Lab KEY

Handout: Beaks and Behavior (1 per pair)

Teacher Resource: PowerPoint: Selective Breeding

Resources

Suggested Websites:

Bear Essentials of Hibernation: http://www.pbs.org/wgbh/nova/nature/bear-essentials-of-hibernation.html

Migratory routes of the Gray Whale: http://www.learner.org/jnorth/tm/gwhale/MigrationRoute_Map.html

Migration of Birds: http://www.npwrc.usgs.gov/resource/birds/migratio/patterns.htm

The Great Migration of Wildebeest and Zebra: http://www.eyesonafrica.net/migration.htm

Nature: Monarch Butterfly Migration: http://www.teachersdomain.org/asset/nat08_vid_monarchmig/

Animal Planet: Bear Hibernation: http://animal.discovery.com/videos/natural-world-bear-hibernation.html

Genetic Variation: https://migrc.org/TeachersAndStudents/GeneticVariation.html

Suggested Books:

Migration:

Berkes, M. (2010). Going home: The mystery of animal migration. Nevada City, CA: Dawn Publishers.

Carney, E. (2010). Great migrations: Whales, wildebeests, butterflies, elephants, and other amazing animals on the move. Des Moines, IA:

National Geographic Children's Books.

Crossingham, J. (2001). What is migration? NY: Crabtree Publishing Company.

Nelson, R. (2010). Migration. Minneapolis, MN: Lerner Classroom.

Rylant, C. (2006). The journey: Stories of migration. NY: The Blue Sky Press.Bancroft, H. (1996). Animals in winter. NY: Collins.

Hibernation:

Crossingham, J. (2001). What is hibernation? NY: Crabtree Publishing Company.

Cyrus, K. and Meadows, M. (2010). Hibernation station. NY: Simon & Schuster Books for Young Readers.

Ganeri, A. (2005). Hibernation. NY: Heinemann-Raintree.

Hall, M. (2008). Hibernation. Mankato, MN: Capstone Press.

Nelson, R. (2010). Hibernation. Minneapolis, MN: Lerner Classroom.

Advance Preparation

1. Prior to Day 1: Prepare four pieces of chart paper by recording the following titles on each:

Selective Breeding

Natural Selection

Genetic Engineering of Crops

Survival Behaviors

Below each title, add the following blurbs and conceal them until time to reveal them during class.

On the Selective Breeding - Breeding for a specific trait

On the Natural Selection - Biological traits become either more or less common in the population.

On the Genetic Engineering of Crops - Genes manipulated to produce disease-resistant plants

On the Survival Adaptations and Behaviors - Camouflage, hibernation, and migration

2. Prior to Day 2: Print and laminate sets of the Teacher Resource: Migration, Hibernation, Dormancy, Phototropism, and Geotropism. You

will need one set per group.

3. Prior to Day 4: Prepare for the Natural Selection lab. Refer to the Teacher Resource: Natural Selection Lab KEY for specific details. Sharpen

one pencil per group. Mix and bag a variety of dry beans for each group of students. Place a minimum five of five different types of beans per

bag for a total of 25 beans. If you are using dowels, sharpen one end of each prior to beginning the activity.

4. Prior to Day 5:

Prepare for the Finicky Finches Lab stations. Refer to the Teacher Resource: Finicky Finches Lab KEY for specific details. Place each food

source into six different foam bowls. Place one bowl at each station. Collect six of each tool to place at each station.

Using district adopted resources or the Internet, locate and preview an article or passage on Galapagos finches. Carefully preview your selection

Grade 7

Science

Unit: 12

Lesson: 02
















http://www.pbs.org/wgbh/nova/nature/bear-essentials-of-hibernation.html

http://www.learner.org/jnorth/tm/gwhale/MigrationRoute_Map.html

http://www.npwrc.usgs.gov/resource/birds/migratio/patterns.htm

http://www.eyesonafrica.net/migration.htm

http://www.teachersdomain.org/asset/nat08_vid_monarchmig/

http://animal.discovery.com/videos/natural-world-bear-hibernation.html

https://migrc.org/TeachersAndStudents/GeneticVariation.html

to ensure that it meets your district’s adopted and approved policies and procedures.

5. Prepare attachment(s) as necessary.

Background Information

This lesson bundles the student expectations that identify and explain variation within a population or species, as well as identifying some changes in genetic traits that have

occurred over several generations through natural selection and selective breeding.

Prior to this unit, students have been introduced to concepts relating to heredity and sexual and asexual reproduction and learned that inherited traits of individuals are

governed in the genetic material found in genes. This material included an introduction to the basic structure of DNA. During this unit, students will learn that physical traits, as

well as some behaviors, are inherited. In previous lessons, students have studied the differences between structure and function and how they are related to each other. This

should help them better be able to understand variations within a population or species. After this unit, these concepts will not be directly taught again in middle school.

STAAR Note: Student expectation 7.11C is a Supporting Standard that will be assessed on the STAAR Grade 8 Science Assessment. This is the last time that genetic variation

and adaptations will be directly taught before the test. In addition, the content of this unit builds a foundation for the material assessed in Reporting Category 2: Mechanisms of

Genetics on the STAAR Biology Assessment.

For further information on genetic variation, please visit the following websites:



INSTRUCTIONAL PROCEDURES

Instructional Procedures

ENGAGE – 4 Corners

Notes for Teacher

NOTE: 1 Day = 50 minutes

Suggested Day 1

1. Introduce the lesson including the following:

During the last lesson, we used physical traits and external structures of

organisms (insects and leaves) to classify them. You will find in this unit

how genetic traits change occur over several generations and how these

variations and adaptations help organisms survive.

What are some genetic traits or adaptations we may see in animals over

several generations? Answers will vary.

What are some genetic traits or adaptations we may see in plants over

several generations? Answers will vary.

2. Prepare the four charts (see Advance Preparation). Before class, place one chart in

each corner of the room. Leave them on the walls, as they will be revisited later in the

lesson.

3. As you move to each corner and read the title aloud, unveil the following details on

each chart:

On the Selective Breeding - Breeding for a specific trait

On the Natural Selection - Biological traits become either more or less common in

the population.

On the Genetic Engineering of Crops - Genes manipulated to produce disease-

resistant plants.

On the Survival Adaptations and Behaviors - Camouflage, hibernation, and

migration.

Do not elaborate further at this point.

4. Explain to students that they will be participating in an activity called “4 Corners”.Inform students that you will read a statement. (Post the statement for students who

are not auditory learners.) They are to think, not talk, about the statement for about

30 seconds.

5. At your signal, students are to move to and stand in the corner that they think is

labeled with the correct answer.

6. The 4 Corners statement is, “The process that best allows a species or population oforganisms to survive is _________.” Remind students to think about it for 30 secondsand move to their selected corner at your signal.

7. Instruct students to talk to the others in their corner as to why they picked that corner.

Students should also select a spokesperson for the group. This person will share the

groups’ thinking with the rest of the class.

Materials

paper (chart, 4 sheets per teacher)

markers (1 per teacher)

timing device (1 per teacher)

Instructional Notes:

There is not a particular correct answer to the statement. As the

lesson progresses, students will learn about each of the topics.

The 4 Corners will be revisited at a later point in the lesson.

STAAR Notes:

Student expectation 7.11C is a Supporting Standards that will be

assessed on the STAAR Grade 8 Science Assessment. This is the

last time that genetic variation and adaptations will be directly taught

before the test. In addition, the content of this unit builds a

foundation for the material assessed in Reporting Category 2:

Mechanisms of Genetics on the STAAR Biology Assessment.

This SE contains new concepts for the students.

Check For Understanding:

The Engage may serve as a pre-assessment to inform the delivery

of the lesson.

Grade 7

Science

Unit: 12

Lesson: 02





8. Facilitate a discussion with each of the 4 Corner groups, allowing each group to justify

their thinking. Instruct students to return to their seats.

EXPLORE/EXPLAIN – Plants Suggested Days 1 (continued) and 2

1. Facilitate a reflective discussion including the following:

In the previous lesson, we examined traits and external structures of

insects and leaves in order to identify them using a dichotomous key.

What are some of the structures you observed that you think may help

plants survive? Answers will vary.

2. Project and distribute the Handout: Plant Advanced Organizer to each student.

Read the titles of the sections on the handout. Point out the section in the bottom,

right hand corner. They will use this information as a guide as they learn about the

structure and function of plants.

3. Say:

As you watch the presentation, you will be looking at variety of structures,

functions, variations, adaptations, and behaviors of plants that help

ensure their survival. As the slides are shown, I will pause after each

section so that you can add information to the advanced organizer about

how each of the variations, adaptations, or behaviors allows plants to

survive.

4. Present the slides of the PowerPoint Plants and Their Adaptations to students.

Ensure that the slides are shown at a pace such that students can add information to

the advanced organizer.

5. As you progress through the presentation, pause and point out each of the external

features (variations and adaptations), behaviors, and physiology that enhance the

survival of the plants. Reference the dichotomous key used in the previous lesson

when discussing leaves. Additional information for students includes:

Roots – Carries water and minerals to plant; gives some support of plant by

anchoring it to the ground; some roots can store food

Stems – Support of plant; moves water from the roots up the plant; moves food

from the leaves down the plant; sometimes have structures for defense of the plant

such as prickles, thorns, bark, or stinging hairs

Leaves – Shapes and size vary, depending on how much sunlight the plant needs;

produce food for the plant; release oxygen; plant defenses such as prickles and

spines

Flowers – Produce fruits which contain seeds; attract pollinators with a variety of

means

Seeds and dispersal – Carry the new plant; have to be spread to keep from

competing with parent plant; seeds can be dispersed by wind, humans, animals,

etc.; seeds have various variations to enable spreading

Phototropism – No matter which way a seed lands or is buried, the leaves will

grow toward the light.

Geotropism – No matter which way a seed lands or is buried, the roots will grow

toward the ground in response to the pull of gravity.

6. Monitor students as they complete their advanced organizers to ensure accuracy of

information and completion of the task.

7. Facilitate a discussion including the following:

What are some of the structures, variations, adaptations, or behaviors

that help ensure a plants’ survival? Answers will vary- shallow roots/deep

roots, thorns/spines, phototropism/geotropism, etc.

How does the environment require plant species to adapt? Answers may

vary.

8. Distribute the Handout: Verbal Visual Vocabulary Cards to each student. Explain to

students that they will only be completing certain portions of the handout at this time.

9. Instruct students to add a visual for each of the terms, and include a way that each

adapts to the environment. Encourage students to use the Handout: Plant Advanced

Organizer for ideas. They will complete the handout during the class on Day 3.

10. Instruct students to affix both the Plant Advanced Organizer and Verbal Visual

Materials


Attachments:

Handout: Plant Advanced Organizer (1 per

student and 1 for projection)

Teacher Resource: PowerPoint: Plants and Their

Adaptations

Handout: Verbal Visual Vocabulary Cards (1 per

student)

Instructional Note:

Consider making a variety of plants with various structures and

behaviors (tropisms) available for students to view, perhaps a plant

by a window and one across the room; a sweet potato in a jar of

water; cactus or succulent, etc.

Science Notebooks:

Students affix both the Plant Advanced Organizer and the Verbal

Visual Vocabulary Cards to their notebooks.

Grade 7

Science

Unit: 12

Lesson: 02



Vocabulary Cards to their notebooks.

EXPLORE/EXPLAIN – Animals Suggested Days 2 (continued) and 3

Facilitate a reflective discussion including the following: (Use various instructional

strategies to increase student engagement and accountability.)

If plants adapt to their environment to enhance their survival, do

animals? Yes

How do you change your behavior when it is very hot outside?

Answers will vary. Allow time for students to respond. Using a strategy, such

as think-pair-share, would give all students the opportunity to express their

thinking.

In what ways do you change the clothing you wear, food you eat, and

activities you do? Answers will vary. Allow time for students to respond.

How do you change your behavior when it is cold outside? Answers

will vary. Allow time for students to respond.

In what ways do you change the clothing you wear, food you eat, and

activities you do? Answers will vary. Allow time for students to respond.

We change our behaviors, such as what we wear, what we eat, and

what we do in response to the environment in which we live.

In what ways do plants adapt to their environment to increase their

chances of survival? Answers will vary- shallow roots/deep roots,

thorns/spines, phototropism/geotropism, etc.

In what ways do you think that animals adapt to their environment to

increase their chances of survival? Answers will vary, depending on

individual student experiences.

Divide students into groups of 2–3.Distribute two sticky notes per group of students.

Instruct students to work with their group to brainstorm the answer to the following

question: (They should write their ideas on the sticky notes.)

In what ways do animals respond to changes in temperature and

weather?

After students have had 2–3 minutes to think and write, ask each group to shareone of their suggestions. Record all responses on the chart paper (see

Instructional Notes).

Student responses will vary depending on prior science instruction. However, the

list may include, but is not limited to:

— migration or movement

— hibernation

— aestivation

— dormancy

— torpidity (a controlled reduction of body metabolism, evidenced by low oxygen

consumption rates and lower body temperatures)

— shedding

— panting

— growing a thicker winter coat

— increased layers of insulating fat

Project and distribute the Handout: Animal Advanced Organizer to each

student. Read the titles of the sections on the handout.

Say:

As you watch the presentation, you will be looking at variety of

structures, functions, variations, adaptations, and behaviors of

animals that help ensure their survival. As the slides are shown, I

will pause after each section so that you can add information to the

advanced organizer about how each of the variations, adaptations,

or behaviors allows animals to survive.

Present the slides of the PowerPoint: Animal Variations and Behaviors to

students. Ensure that the slides are shown at a pace such that students can add

information to the advanced organizer.

As you progress through the presentation, pause and point out each of the

structures, functions, variations, adaptations, and behaviors that allow the survival

of the animals. Additional information for students includes:

Camouflage – Allows an animal to blend with its surroundings; allows some

animals to catch their food; allows some animals to avoid becoming food for

other animals

Structure – What the form or shape of part(s) is (are) of an organism such

as mouthparts, appendages, etc.

Function – What the part(s) of an organism do; the job they perform

Materials:

chart paper (1 per class)

marker (1 per teacher)

sticky notes (3”x3”, 2 per group)cardstock (1 half sheet per student)


Attachments:

Handout: Animal Advanced Organizer (1 per


Teacher Resource: PowerPoint: Animal Variations

and Behaviors

Optional Teacher Resource: Migration and

Hibernation SAMPLE

Teacher Resource: Migration, Hibernation,

Dormancy, Phototropism, Geotropism

(see Advance Preparation, 1 set per group)


Record all student thinking on the chart. The responses could be

categorized using a T-chart. After all of the responses have been

recorded, ask students to identify the label for each column.

The two columns would be labeled cold weather responses and

hot weather responses.

Science Notebooks:

Students affix Handout: Animal Advanced Organizer to their

notebooks.

Grade 7

Science

Unit: 12

Lesson: 02



Mouthparts – The parts found in and around the mouth are specialized in

structure for the function that they have to perform. Mouthparts vary from

species to species and are directly related to the type of food the organism

eats.

Appendages – A part or organ, such as an arm, leg, tail, antennae, wings,

or fin, that is joined to the trunk of a body

Migration – The regular, periodic movement of all or part of a population of

animals from the place where it has been living to a new area and its later

return journey to the original home; usually seasonal to find abundant food,

water, tolerable climate or a good place to breed

Hibernation – The inactive or resting state in which some animals pass the

winter

Monitor students as they complete their advanced organizers to ensure accuracy

of information and completion of the task.

Facilitate a discussion about variations, adaptations, and behaviors that enhance

an animal’s survival. The Optional Teacher Resource: Migration and

Hibernation SAMPLE may be used to enhance the discussion.

Include the following:

How do animal behaviors, such as hibernation or migration, enhance

their survival?

What are some variations and adaptations that increase an animal’schances of survival?Distribute the Teacher Resource: Migration,

Hibernation, Dormancy, Phototropism, and Geotropism (see Advance

Preparation) to pairs of students.

Students can use the illustrations on the cards to assist with the completion of the

terms on the Handout: Verbal Visual Vocabulary Cards.

Collect the Migration, Hibernation, Dormancy, Phototropism, and

Geotropism card sets.

EXPLORE/EXPLAIN – Variation Lab Suggested Day 3 (continued)

1. Introduce the investigation including the following:

We have studied how variations, adaptations, and behaviors in plants and

animals enhance their survival.

Why do these variations, adaptations, and behaviors occur? They are

genetically passed down through generations.

How do these traits get passed from one generation to the next? The

organisms with traits most fit for survival will survive to reproduce, and those traits

are passed on to their offspring through the genes.

How do changes in populations and species occur over time? The

organisms with traits most fit for survival will survive to reproduce, and those traits

are passed on to their offspring through the genes. The traits most fit for survival in

certain conditions get passed down to offspring and the process continues.

Eventually, this may result in variations within species and populations.

2. Project and distribute the Handouts: Variation Lab and Island Strawling Bird Data

Sheet to each student.

3. Explain the expectations to the class, and answer any questions students may have.

(You may need to model how to record data on the data sheet.) Review safety

procedures and acceptable guidelines for testing the flight of their “birds” at this time.

4. Divide the class into groups of 4–5.

5. Distribute materials to each group of students.

6. Instruct students to work with their group to complete the investigation, including the

Handout: Island Strawling Bird Data Sheet and the questions in the conclusions

and analysis on the Handout: Variation Lab.

7. Monitor student groups, and facilitate by asking Guiding Questions.

8. After students have completed the questions on the Handout: Variation Lab, facilitate

a discussion about variation. Include the following:

How do genetic traits change over several generations?

How does variation within a population or species enhance their

survival?

If variations in populations and species enhances their survival, how

does biodiversity contribute to the sustainability of an ecosystem overall?

Members of a species are alike in many ways. However, individuals within

Materials:

paper (plain, 4 sheets per group)

tape (clear, 1 roll per group)

straws (not flexible, 4 per group minimum)

ruler (1 per group)

scissors ( 2 pairs per group)

penny (1 per group)

six-sided number cube (1 per group)


Attachments:

Handout: Variation Lab (1 per student and 1 for

projection)

Handout: Island Strawling Bird Data Sheet (1 per


Teacher Resource: Variation Lab KEY

Safety Notes:

Students should wear safety goggles.

Students should not engage in horseplay while testing their “birds”.

STAAR Note:

TEKS/SE 7.11C contains new concepts for the students, and they

are not directly taught again before the STAAR test is given in Grade

8.


The reflective questions are an opportunity to informally assess

Grade 7

Science

Unit: 12

Lesson: 02



a species show small differences.

Variations are differences in appearance of an inherited trait among the

members of a species.

Variations can be observed in traits related to size, shape, behavior,

structure, function, and parts.

Variations are inherited and can be passed down to the offspring from the

parent organism.

Variations in individuals may affect their ability to survive in a changing

environment.

During the course of many generations, a variation that provides a

survival advantage can become widespread in a population because

individuals within it have a higher probability of reproducing.

Variation in species ensures survival of the species.

9. Instruct students to work with a partner to answer the following reflective questions in

their notebooks.

How do genetic traits change over several generations?


survival?

If variations in populations and species enhances their survival, how

does biodiversity contribute to the sustainability of an ecosystem overall?

10. Monitor students, and assist as needed.

11. Ask for volunteers to share their responses with the class. Clarify any misconceptions.

12. Instruct students to clean up their area.

student understanding of this concept.

Science Notebooks:

Students affix their Variation Lab and Data Sheets to their

notebooks.

Students record reflective questions and answers in their

notebooks.

EXPLORE – Natural Selection Lab Suggested Day 4

1. Project and distribute the Handout: Natural Selection Lab (see Advance

Preparation) to each student. (Review the Teacher Resource: Natural Selection Lab

KEY prior to beginning this activity. Suggestions for alternate materials are included

on the KEY.)

2. Explain the expectations, review safety guidelines regarding sharp objects, and

answer any questions students may have. (You may wish to model an example with

the data table.)

3. Divide students into groups of 3–4, and distribute materials.

4. Monitor student groups, and assist as needed.

5. Instruct students to affix their Handout: Natural Selection Lab and their graphs to

their notebooks.

6. Instruct students to place all beans back inside the bags and clean up their area.

Materials:


foam bowl (large,1 per group)

pencil (sharpened, 1 per group)

newspaper (1 sheet per group)

pointed objects (4 different diameters, per group)

resealable plastic bag (snack-size, 1 per group)

beans (dried, 5 different types, 5 cups total, 5 of

each type per group minimum)


paper (graph, 1 per student)

Attachments:

Handout: Natural Selection Lab (1 per student

and 1 for projection)

Teacher Resource: Natural Selection Lab KEY

Safety Notes:

Remind students to be cautious with sharp objects when poking

holes in the bowls. Students should never point a sharp object at

another person. Safety goggles should be worn while using sharp

instruments.

Instructional Note:

(Review the Teacher Resource: Natural Selection Lab KEY prior to

beginning this activity. Suggestions for alternate materials are

included on the KEY.)

STAAR Note:



8.

Grade 7

Science

Unit: 12

Lesson: 02



Science Notebooks:

Students affix the Handout: Natural Selection Lab and their graphs

to their notebooks.

EXPLAIN – Natural Selection Suggested Day 4 (continued)

1. Facilitate a reflective discussion including the following:

What was the trait that allowed some of your organisms to survive?

Answers will vary, depending on the lab students discuss; however, in the

Variations Lab, survival depended on the wing size. In the Natural Selection Lab, it

was because the bean was larger than the hole in the bowl.

Did more than one type of organism survive? Answers may vary, but probably

there were more than one type of organism that survived.

Were their characteristics the same? (They were similar, but not the same.)

How does this mimic what occurs in real life? Each species will fill an

ecological niche and not compete with other species. Many species can survive if

they are not competing for the same resources.

How do genetic traits change over several generations? The organisms

with traits that are most fit for survival are most likely to reproduce, and the traits

continue to get passed on to offspring.


survival? Organisms that survive to reproduce pass those traits on to their

offspring. Over time, as a need to adapt to certain conditions, variations result.

Those variations make it more likely for those organisms to reproduce.

Living organisms that are best suited for their environment adapt,

survive, and reproduce.

Those that do not, die.

This is known as natural selection.

Traits necessary for survival are passed through a population.

The surviving population has traits that are different than the original

population.

What role do traits play in natural selection? Traits necessary for survival are

passed through the population, and the surviving population develops different

traits than the original population.

2. Project the Teacher Resource: Natural Selection Process to students.

3. Select students to read each of the text boxes in the flow chart.

4. Instruct students to write and/or draw a summary of the natural selection process in

their notebooks.

Attachments:

Teacher Resource: Natural Selection Process (1

for projection)


The summary provides the teacher with an opportunity to informally

assess student understanding of this concept.

Science Notebooks:

Students write and/or draw summaries in their science notebooks.

EXPLORE/EXPLAIN – Galapagos Finches Suggested Day 5

1. Project and distribute the Handout: Finicky Finches Lab (see Advance Preparation)

to each student. (Review the Teacher Resource: Finicky Finches Lab KEY prior to

beginning this activity for the set up and management of stations.)

2. Explain the expectations, review safety guidelines, and answer any questions students

may have.

3. Divide students into six groups, and assign groups to a station at which they will begin

the lab investigation.

4. Briefly review the station procedures if clarification is needed, and signal students to

move to their assigned station.

5. Monitor student progress at the stations. (Each station should only take about five

minutes.)

6. When students have rotated through all stations and returned to their seats, distribute

the Handout: Beaks and Behavior to each pair of students. Instruct students to work

with their partner and use the pictures to complete their charts.

7. Monitor and facilitate student work as the charts are being completed.

8. Instruct students to affix the Handout: Finicky Finches Lab to their notebooks.

9. Using district adopted resources or the Internet, locate and preview an article or

passage on Galapagos finches to further develop students’ background knowledgeon natural selection (see Advance Preparation).

10. The following questions may be used to facilitate a discussion on the topic of

Galapagos finches:

Materials:

dried lima beans (1 bag per class)

mini-marshmallows (1 bag per class)

finch or small bird seed (1 box per class)

raisins (1 box per class)

yarn (cut into 4 cm pieces, several per class)

jelly beans or gum drops (1 bag per class)

pliers (1 per group)

clothespins (spring-type, 1 per group)

tweezers or forceps (1 per group)

chopsticks (with pointed ends, 1 per group)

binder clips (1 per group)

alligator clips (hardware-type, 1 per group)

foam bowls (1 per group)

toothpicks(round, 6 per class)

timing device (1 per group)

cups (paper, small, 1 per group)

colored pencils (1 package per group)


Attachments:

Handout: Finicky Finches Lab (1 per student and

1 for projection)

Teacher Resource: Finicky Finches Lab KEY

Grade 7

Science

Unit: 12

Lesson: 02



What were some characteristics the finches developed to give them an

advantage in surviving? Beak shapes, lengths, and functions gave them an

advantage in the competition for resources.

How do you think that the one species of finch developed into many

different species, each with its own advantages? By the reproducing of the

best adapted finches in order to fill a niche to survive. This is survival of the fittest

through natural selection.

In what ways do these advantages helped the finches survive and

reproduce? The islands are too small to support only one type of bird. They

would all be competing for the same food source. By developing different beaks,

the finches were able to take advantage of a variety of food sources.

What might have happened if the finches didn't develop into many

different species? The entire species would go extinct.

Handout: Beaks and Handout: Beaks and

Behavior (1 per pair of students)

Safety Note:

Remind students to be cautious with sharp objects when poking

holes in the bowls. Students should never point a sharp object at

another person. Safety goggles should be worn while using sharp

instruments.


This lab should be completed in one day. Once the students get

through their first station, they should not need practice time with the

tools.

Misconception:

Students may think that adaptations result from

some overall purpose or design or they describe

adaptation as a conscious process to fulfill some

need or want.

STAAR Note:



8.

Science Notebooks:

Students affix the Handout: Finicky Finches Lab to their notebooks.

EXPLORE/EXPLAIN – Selective Breeding Suggested Day 6

1. Project and play the PowerPoint: Selective Breeding to students.

2. As you progress through the slides, instruct students to define selective breeding,

create a T-chart to list advantages and disadvantages, and list examples in their

notebooks.

3. Facilitate a discussion including the following questions:

Do any of you have pets or raise livestock that have been selectively

bred? Responses will vary. The most common animals will be pure bred dogs,

such as Chihuahuas or Dachshund, and 4-H cattle, pigs, sheep, or poultry.

In what ways are defects caused by too much selective breeding? In dogs,

hip dysplasia in large dogs, epilepsy in cocker spaniels, breathing problems for

pugs, and hearing loss for Dalmatians are common.

What are some positive aspects of selective breeding? Answers will vary,

but may include size, strength, calmness, drought tolerant, disease resistant, less

fat, etc.

What role do traits play in selective breeding? Desired traits in organisms are

selected and bred for. Those traits get passed on to their offspring.

What evidence do we have that traits of organisms have changed over

time? Galapagos finches and selective breeding

How are natural selection and selective breeding similar and different?

Selective breeding is goal oriented. Humans select the traits they desire and breed

organisms for them. Natural selection occurs in nature when organisms most

suited to their environment reproduce and pass on those traits to their offspring.

Traits necessary for survival are passed through the population, and the

surviving population develops different traits than the original population.

4. Instruct students to compare and contrast natural selection and selective breeding in

their notebooks, including one advantage and one disadvantage of selective

breeding.

Attachments:

Teacher Resource: PowerPoint: Selective

Breeding

Instructional Note:

Be sure that students understand that selective breeding has both

positive and negative aspects.

STAAR Note:



8.


The activity provides the teacher with an opportunity to informally


Science Notebooks:

Students define selective breeding, create a T-chart to list

advantages and disadvantages, and list examples in their

notebooks.

Students compare and contrast natural selection and selective

breeding in their notebooks, including one advantage and one

disadvantage of selective breeding.

ELABORATE Suggested Day 6 (continued)

1. Revisit the 4-corners activity. Post the signs used in the Engage activity. This activity

should take no more than 10 minutes to complete. Materials

Grade 7

Science

Unit: 12

Lesson: 02



2. Inform students that you will read a statement. They are to think, not talk, about the

statement for about 30 seconds. At your signal, students are to move to and stand in

the corner that they think is labeled with the correct answer.

3. The 4 Corners question is, “The process that best allows a species or population oforganisms to survive is _________.”

4. Instruct students to talk to the others in their corner as to why they picked that corner.

Students should also pick someone speak for the group and share their answer with

the rest of the class.

5. Rotate through the corners, and ask for student volunteers to share their reasons for

choosing that corner. Also, ask if the corner that they chose this time was different

from the one that they chose the first time through this activity.

6. Instruct students to return to their seats.

7. Instruct students to reflect in their science notebooks on the process that best allows

a species, population, or organism to survive.

8. Facilitate a class discussion in which students will volunteer to share out with the

class.

4 Corners posters from Engage activity


Again, there is not only one correct answer. Several processes,

such as natural selection, adaptations, and behaviors, aid in

survival. The least helpful corners for survival are selective breeding

and genetic engineering. Both of these require human intervention.

Point out that many “purebred” breeds of dogs have health

problems due to selective breeding.

Students should be grouped more in the natural selection and

survival behavior corners.


The activity provides the teacher with an opportunity to informally


Science Notebooks:

Students reflect on the process that best allows a species,

population or organism to survive.

EVALUATE – Performance Indicator Suggested Day 7

Grade 07 Science Unit 12 PI 02

Create an advertisement for a genetic engineering firm. In the advertisement, compare natural

selection to selective breeding, and explain how variation in the species enhances its survival.

Standard(s): 7.2E , 7.11B , 7.11C

ELPS ELPS.c.5F , ELPS.c.5G

1. Project the Performance Indicator on the board.

2. Share the Performance Indicator rubric or your expectations with students prior to

students beginning the assessment.

Say/Ask:

Genetic engineering is the modification of an organism’s characteristics(traits) by the manipulation of its genetic material.

Genetic engineering allows scientists to develop traits that may help an

organism better survive in certain conditions.

What are some conditions that are harsh on some organisms? Answers will

vary, but may include drought, temperature, disease, etc.

Your advertisement should be persuasive as to why genetic engineering

may be beneficial to organisms.

Include a comparison of natural selection and selective breeding.

Explain how variation in a species will enhance its survival

3. Answer and questions students may have. Some students may benefit from an

example of an advertisement.

4. Students will create their own advertisement.

5. Instruct students to decide on the format for their advertisement such as a flyer,

poster, 3D display, etc. (see Instructional Notes).

6. Students must now decide if the genetic engineering firm will focus on plants or

animals.

7. Instruct students to reference their notebooks to assist them in the development of

their advertisement.

8. Monitor and assist as needed.


If the advertisement can’t be finished during the class period, the

students should have the opportunity to complete the project

outside of class time.

You may wish to allow students to complete the Performance

Indicator with a partner.

Encourage students to reference their science notebooks.

Grade 7

Science

Unit: 12

Lesson: 02








Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 1 of 1

Plant Advanced Organizer

Tropism: Plant movement

(behavior) triggered by stimuli Plant Structures

Leaves

Seeds

Roots

Geotropism

Phototropism

Stems

Flowers Seeds Include the following for each of the plant structures listed: Function: Variations: Adaptations:

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 1 of 2

Verbal Visual Vocabulary Cards

Physiology

Phototropism

Geotropism

External Features

The scientific study of an organism's vital functions,

including growth and development

Movement or growth in response to lights or

colors of light

A plant whose roots grow down into the soil as a

response to gravity

The outward appearance of a distinct part that can

be seen, such as the roots, stem, leaf, or flower

of a plant

Function

Adaptation

Variation

Behavior

The physiological activity of a part (the specific role a part has in the system)

The process of changing in response to something, such as an environmental

condition

Marked difference or deviation from the normal

or recognized form, function, or structure

The actions and mannerisms made by

organisms in response to their environment. It is

sometimes a response to various stimuli.

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 2 of 2

Structure

Camouflage Migration Hibernation

The arrangement of and relationship between the parts of something; made up of a number of parts

that are held or put together in a particular

way

A method of concealment that allows an otherwise visible animal to remain unnoticed by blending with its environment

The relatively long-distance movement of

individuals, usually on a seasonal basis

Hibernation is a state of inactivity and decreased metabolism in animals,

characterized by lower body temperature, slower

breathing, and/or lower metabolic rate. Hibernation during summer months is

known as aestivation.

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 1 of 1

Animal Advanced Organizer

Migration Structure:

Function:

Hibernation

Mouth Structures

Camouflage

Appendages

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 1 of 1

Migration and Hibernation SAMPLE

Migration Hibernation

Birds, mammals,

fish, reptiles,

amphibians,

insects, and

crustaceans are

found to migrate.

Relatively

long-

distance

movement

Trigger may be

climate

Trigger may be

local availability

of food

Trigger may be

the season

Annual or

seasonal

occurrence

Movement leads to the redistribution of individuals within a population.

Within a migratory

species or even

within a single

population, often

not all individuals

migrate.

A state of inactivity and

decreased metabolism in

animals, characterized by

lower body temperature,

slower breathing, and/or

lower metabolic rate

Can include torpor and

aestivation

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 1 of 4

Migration, Hibernation, Dormancy, Phototropism, and Geotropism

Migration

salmon

dolphin

Mexican free-tailed bats

monarch butterflies

whale

arctic tern

http://upload.wikimedia.org/wikipedia/commons/c/c1/Jumping_Salmon.jpg

http://upload.wikimedia.org/wikipedia/commons/1/19/Tadarida_brasiliensis_outflight_Hristov_Carlsbad_Caverns.jpg

http://upload.wikimedia.org/wikipedia/commons/0/05/Monarch_butterflies.jpg
















Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 2 of 4

Hibernation

brown bear

hedgehog

kangaroo rat

squirrel

Dormancy

snake

frog

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 3 of 4

skunk

badger

turtle

ladybug

Phototropism

http://commons.wikimedia.org/wiki/User:Tangopaso

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 4 of 4

Geotropism

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 1 of 3

Variation Lab Introduction: The Island Strawling bird lives on a remote island in the South Pacific. It feeds on strawberries and drinks from the freshwater lakes that are sparsely located on the island. Only those birds that can accomplish the lengthy flight from freshwater lake to freshwater lake will live long enough to breed successfully. In this lab, you will breed several generations of the Island Strawling bird and observe the effects of various changes in genetic traits that can occur through natural selection.

Materials (per group):

Safety: Students should wear safety goggles. Students should not engage in horseplay while testing their “birds”. Procedure: 1. Prepare the parent bird:

Cut two strips of paper, each 3 cm x 30 cm. Loop one strip of paper with a 1 cm overlap, and tape the ends together with a small

(approximately 1 ½ cm) piece of tape. Repeat this with the other strip. Tape each loop 3 cm from the end of the straw.

2. Breed the offspring. ( Each bird lays a clutch of three eggs.)

Record the dimensions of each chick, and hatch the birds using these instructions:

— The first egg has no mutations. It is a clone of the parent. (In the interest of time, you may

substitute the parent when testing this chick.)

— The other two chicks have mutations.

— For each chick, flip your coin, throw your die, and then record the results on the table.

— The coin flip determines where the mutation occurs: the head or the tail (heads = head end,

tails = tail end).

paper (4 sheets) cellophane (clear) tape straws (at least 4) ruler (1) six-sided number cube (1)

scissors (2 pairs) safety goggles

penny (1)

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 2 of 3

3. The die throw determines how the mutations affect the wings.

1

The wing moves 1 cm toward the end of the straw.

2

The wing moves 1 cm away from the end of the straw.

3

The circumference of the wing increases 2 cm.

4

The circumference of the wing decreases 2 cm.

5

The width of the wing increases 1 cm.

6

The width of the wing decreases 1 cm.

4. To test the birds:

Release the birds with a gentle, overhand pitch.

It is important to release the birds as uniformly as possible.

Test each bird twice.

5. The most successful bird is the one which can fly the farthest. Write some kind of mark on the wing

of the chick that was the most successful (flew the furthest).

6. The most successful bird is the sole parent of the next generation. Continue to breed, test, and record data for as many generations as you can in the class period.

Results:

Use the Handout: Island Strawling Bird Data Sheet to record the results of your coin flips and die

throws, the dimensions of all chicks, and the most successful bird in each generation.

Conclusions and Analysis:

Answer the following questions in your science notebook. Use complete sentences.

1. Did your experiment result in better flying birds?

2. Evolution is the result of two processes: variation and selection.

a) How did your experiment produce variation among the offspring?

b) How did your experiment select offspring to breed the next generation?

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 3 of 3

3. Compare your youngest bird with your neighbor’s youngest bird.

a) Compare and contrast the wings of other birds with your own.

b) Explain why some aspects of the birds are similar.

c) Explain why some aspects of the birds are different.

4. Predict the appearance of your youngest bird’s descendants if. . .

a) the selection conditions remain the same and the longest flying bird survives to produce the

most offspring.

b) the selection conditions change so that the worst flying bird survives to produce the most

offspring.

c) the selection conditions change and the bird whose color blends with its environment survives

to produce the most offspring.

5. What can you infer about the variation within a species?

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 1 of 4

Natural Selection Lab KEY

Materials: mixed dry beans (5 cups) Choose five types of beans from the following: lentils, pinto, black, navy, red, great

northern beans, split green, and black-eyed peas work well. Be sure to have a variety of sizes. Lima and garbanzo beans tend to block the holes and are not suggested. Multi-bean soup mixes can be used, but may be more expensive than single bags of dry beans.

Beads of different colors and sizes may be substituted for beans. Mix the dry beans/peas together in a large bowl or container. Bag some bean mixture in

a snack-size, plastic bag for each pair of students. Ensure that there is a minimum of five of each type of bean in the bag.

snack-size, plastic bag foam bowl Use the largest diameter available. Clean, foam meat trays may be substituted for the bowl. pencil sheet of newspaper dowels or pointed objects with different diameters (4–5) May use large and small diameter skewers, chopsticks with a point, large diameter

(kinder) pencils, standard pencils, etc. If you use dowels, sharpen the end of regular dowels to making poking the holes in the

foam easier. A small diameter dowel may be sharpened with a pencil sharpener and the larger ones with a knife. Sharpening should be done by the teacher prior to activity.

Objects used for making holes should not all be larger than your largest type of bean. graph paper safety goggles

Safety: Remind students to be cautious with sharp objects when poking holes in the bowls. Students should never point a sharp object at another person. Safety goggles should be worn while using sharp instruments. Procedures: 1. Work in groups. Gather a bag of beans, a foam bowl, a sheet of newspaper, and four objects with

a point for each pair of students. 2. Place your pencil point in the bottom of the foam bowl, and carefully punch a hole through the

bottom of the bowl. The hole should be made so that the rough edge of the hole is outside of the bowl.

3. Fold a sheet of newspaper in half, and place it on the work surface. Set the bowl down on the

newspaper. 4. Place a handful of beans in the bowl. Lift the bowl, and shake it right and left for 15 shakes. 5. Observe the beans that fell through the hole along with the ones that remain in the bowl.

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 2 of 4

Which beans fell through the hole? (The type of bean will vary depending on your mixture. Students should realize that the smaller beans fell through the hole.)

Why did those fall through? (The beans that fell were smaller than the hole.) Why didn’t the other beans do the same? (The beans that remained in the bowl were larger

than the hole.) The beans represent a population of a species. For a species to survive, it must reproduce.

Only those beans that remain in the bowl can reproduce. What characteristic might the next generation of beans have? (The beans would probably be larger than the hole in the bowl allowing them to survive.)

6. Place all of the beans back in the bag. 7. Use four of the objects with a point to poke more holes through the bottom of the bowl. Make each

of the holes a different size, but no hole may be larger than your biggest bean. 8. Select five beans of each type from your bag. Place this population of 25 beans in the bowl.

9. Shake the bowl side to side 15 times, and record the: type and number of beans that fell through the holes. These beans died. type and number of beans that remain in the bowl. These beans lived. number that starts each generation by taking the number that lived and multiplying it by two. Inform students that only the beans that survived can reproduce. The beans that remained in the bowl are the first generation and will represent the parents for the next generation. Remind students that the beans represent organisms in a population.

10. For each of the beans that remain in the bowl, add another one of the same type to show the bean reproduced. If necessary, give students a few more beans if they run out of beans to add. 11. Repeat steps 9 and 10 for a total of five generations. Remember to add the same number and

type of remaining beans after each trial and record the data in the table. 12. Analyze the data, and answer the following questions.

Look at the 1st Generation data. Did all of the types of beans fall out in the same numbers? (Answers may vary, but generally the response should be that the smaller beans fell out more than the larger beans did.)

Look at the starting numbers of each generation. Do the proportions of kinds of beans change? Explain. (Answers may vary, but lead students to the conclusion that the beans larger than the holes are more plentiful than smaller beans. In the beginning, there were five of each type of bean so the proportions were equal. Later the proportions changed.)

What would the data look like if the holes were all larger than the largest beans? (All of the beans would pass through, and there would be no beans left to reproduce. The species would die out. The data would only fill one or maybe two columns.)

What would the data look like if the holes were all smaller than the smallest bean? (None of the beans would pass through, and all of the beans would reproduce causing many more beans in the bowl. There may be more species than can be supported by the bowl, and some could die out. The data would consist of very large numbers of beans.)

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 3 of 4

13. Create a bar graph of the bean that survived the best based on your data. Reproduction numbers for each generation go on the x-axis, and population goes on the y-axis. Graphs will vary.

14. Look at the pattern of your data on the graph. Predict the numbers of the next two generations

if the trend continues. Answers will vary depending on data.

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 4 of 4

Natural Selection Lab KEY

Data Table

Starting Number

Type of Bean

1st

Generation

(Multiply “Live” number by 2 to fill in “ #” column)

2nd

Generation

(Multiply “Live”

number by 2 to fill in “ #” column)

3rd

Generation



4th

Generation



5th

Generation



25 Die Live # Die Live # Die Live # Die Live # Die Live #

5

5

5

5

5

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 1 of 1

Natural Selection Process

Organisms survive and

reproduce, passing on

the genetic information

of the species to the

next generation.

Lack of resources

creates competition

for food and water.

Some organisms die. The

ones that survive were

more suited to their

environment.

Species doing this tend to

produce more offspring

than the environment can

support.

Charles Darwin called the

ability to biologically

adapt to hard times

“survival of the fittest”.

The most desirable traits are

favored, and organisms who

have these traits (adapted)

survive to pass their genes on

to the next generation.

A changing environment

would mean that different

traits would be favored.

Darwin believed that organisms

changed to suit their

environments and occupy an

ecological niche for the best

chance for survival.

Being the fittest is not

always the biggest or

strongest. Some organisms

are “the fittest” because,

rather than compete with

other organisms, they

cooperate with them.

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 1 of 3

Finicky Finches Lab

Materials:

dried lima beans (1 bag) pliers (6 pairs) Styrofoam™ bowls (6) mini-marshmallows (1 bag) spring-type clothespins (6) toothpicks (6) finch or small bird seed (1 box) tweezers or forceps (6) timers/stopwatches (6)

raisins (1 box) jelly beans or gum drops (1 bag) yarn (cut into 4 cm pieces) alligator clips (hardware-type) (6)

chopsticks pointed ends (6 pairs) binder clips (6) safety goggles (1 per student)

small, paper cups (“stomach”)(6)

colored pencils (1 pkg per group)

Safety: Remind students to be cautious with sharp objects when poking holes in the bowls. Students should

never point a sharp object at another person. Safety goggles should be worn while using sharp instruments.

Procedure:

1. Rules for gathering food: Food must be collected in a safe manner. Collect only one piece of food at a time. You may use two hands to operate the beaks but you cannot touch the food with your hands. Food must be transferred to the “stomach” (paper cup) by only using the beak.

2. At the teacher’s signal, go to your assigned station. You will have 30 seconds to gather as many seeds

possible. Repeat the process for each type of beak. 3. At your first station only, you may practice with each tool three times each before setting the timer. Set

the timer for 30 seconds, and begin collecting food. When the timer sounds, stop collecting. Count how many seeds are in the “stomach”, and record the data on the graph.

4. Return seeds to the bowl. Practice with the next tool three times, reset the timer, and collect food. Count

the seeds, and record the data on the graph. Repeat this process until all six beaks have been tested, except for the binder clip and toothpick.

5. When you test the binder clip, use the clip to hold a toothpick. Then, use the toothpick to pick up the

pieces of food. The toothpick represents a tool used by the bird to get its food.

6. At the teacher’s signal, move to the next station, and repeat the process of collecting, counting, and graphing. When you have rotated through all six stations, return to your seat.

7. Look at the Handout: Beaks and Behavior. Carefully observe the finch beaks. Match the simulated

beaks to the real beaks. Match the types of foods that you collected to the real food for the finches.

Galapagos Finch Simulated Beak Real Beak Type Simulated Food Real Food

Large Ground Finch

Vegetarian Tree Finch

Woodpecker Finch

Warbler Finch

Large Tree Finch

Cactus Ground Finch

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 2 of 3

Finicky Finches Lab

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6

Alligator clip- hardware

Type of Food: Small bird seed

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6


Type of Food: Lima beans

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6


Type of Food: Mini-marshmallows

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6


Type of Food: Raisins

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 3 of 3

Finicky Finches Lab

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6


Type of Food: Yarn

Class Graph:

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick

5 Binder clip

6 Alligator clip-

hardware Type of Food: Jelly beans or gum drops

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6


Type of Food:

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6


Type of Food:

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 1 of 4

Finicky Finches Lab KEY

Materials:

dried lima beans (1 bag) pliers (6 pairs) Styrofoam™ bowls (6)

mini-marshmallows (1 bag)

finch or small bird seed (1 box)

spring-type clothespins (6)

tweezers or forceps (6)

toothpicks (6)

timers/stopwatches (6)

raisins (1 box)

jelly beans or gum drops (1 bag)

chopsticks pointed ends (6

pairs)

small, paper cups

(“stomach”) (6)

yarn (cut into 4 cm pieces)

alligator clips (hardware-type)(6)

binder clips (6)

safety goggles (1 per student)

colored pencils (1 pkg per

group)

Safety: Remind students to be cautious with sharp objects when poking holes in the bowls. Students should

never point a sharp object at another person. Safety goggles should be worn while using sharp instruments.

Teacher Preparation:

1. Set up six stations. Place one type of food in each foam bowl. Each bowl is a station.

2. Place one small, paper cup at each station. This represents the “stomach” of the bird.

3. Gather beak simulators, and place them at each station. The simulators represent types of finch

beaks. Each station should have a pair of regular pliers, a spring-type clothes pin, a pair of

tweezers or forceps, a pair of chopsticks with pointed ends, a binder clip (office type for holding

papers), and an alligator clip (hardware-type for attaching wires to). These long-nose alligator clips

are sold in hardware stores near electrical/wires. They can also be found in automotive sections of

discount stores.

4. Divide the class into six groups. Assign each group to a station at which to start the activity.

Review operation of the timing device with students.

5. Inform students that the seeds are types of food and the tools simulate different types of beaks.

The paper cup represents the bird’s stomach. Group members should take turns getting food so

that all participate in this activity.

Procedure:

1. Rules for gathering food: Food must be collected in a safe manner. Collect only one piece of food at a time. You may use two hands to operate the beaks, but you cannot touch the food with your hands. Food must be transferred to the “stomach” by only using the beak.

2. At the teacher’s signal, go to your assigned station. You will have 30 seconds to gather as many seeds

possible. Repeat the process for each type of beak. 3. At your first station only, you may practice with each tool three times each before setting the timer. Set the

timer for 30 seconds, and begin collecting food. When the timer sounds, stop collecting. Count how many seeds are in the “stomach”, and record the data on the graph.

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 2 of 4

4. Return the seeds to the bowl. Practice with the next tool three times, reset the timer, and collect the food. Count the seeds, and record the data on the graph. Repeat this process until all six beaks have been tested, except for the binder clip and toothpick.

5. When you test the binder clip, use the clip to hold a toothpick. Then, use the toothpick to pick up the pieces

of food. The toothpick represents a tool used by the bird to get its food. 6. At the teacher’s signal, move to the next station, and repeat the process of collecting, counting, and

graphing. When you have rotated through all six stations, return to your seat.

7. Look at the Handout: Beaks and Behavior. Carefully observe the finch beaks. Match the simulated beaks to the real beaks. Match the types of foods that you collected to the real food for the finches.

Galapagos Finch Simulated Beak Real Beak Type Simulated Food Real Food Large Ground Finch

Pliers Crushing Dried beans Large, hard seeds


Clothespin Crushing Mini-marshmallows Plant parts

Woodpecker Finch Alligator clip (hardware-type) and toothpick

Grasping Yarn Grubs hidden in trees

Warbler Finch Tweezers Probing Small bird seed Insects in holes

Large Tree Finch Binder clip Crushing Raisins Insects

Cactus Ground Finch

Chopsticks (pointed) Stabbing Jelly beans or gum drops

Cactus parts and insects

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 3 of 4

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6

Alligator clip-

hardware Type of Food: Small bird seed

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6

Alligator clip-

hardware Type of Food: Lima beans

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6

Alligator clip-

hardware Type of Food: Mini-marshmallows

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6

Alligator clip-

hardware Type of Food: Raisins

Data for these six

graphs will vary,

depending on the

students’ skill.

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 4 of 4

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6

Alligator clip-

hardware Type of Food: Yarn

Class Graph: Choose two types of food, and create two class graphs. Ask each group for their totals, and allow students to compare

their data.

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6

Alligator clip-

hardware Type of Food: Jelly beans or gum drops

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6

Alligator clip-

hardware Type of Food:

12 11 10 9 8 7 6 5 4 3 2 1 0 1

Pliers 2

Clothespin 3

Tweezers 4

Chopstick 5

Binder clip 6

Alligator clip-

hardware Type of Food:

Data will vary depending on food chosen. Data will vary depending on food chosen.

Grade 7 Science

Unit: 12 Lesson: 02

©2012, TESCCC 02/11/13 page 1 of 1

Beaks and Behavior

Crushing Beak for Hard Seeds

Large Ground Finch

Crushing Beak for Plants, Fruit Buds, or Leaves


Grasping Beak Using Tools to get Grubs

Woodpecker Finch

Probing Beak for Insects in Holes

Warbler Finch

Crushing Beak for Insects

Large Tree Finch

Stabbing Beak for Cactus Parts

and Insects

Cactus Ground Finch

http://commons.wikimedia.org/wiki/File:Darwin%27s_finches_by_Gould.jpg

http://commons.wikimedia.org/wiki/File:CactornisPallidaPZSL1870.jpg

http://commons.wikimedia.org/wiki/File:CerthideaFuscaPZSL1870.jpg

science grade 07 unit 12 exemplar lesson 02: changes in ...staar note: student expectation 7.11c is...

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